During the process of constructing bituminous pavements hand tools such as rakes (referred to as lutes), shovels, and scrapers become coated with the bituminous mixture. Common practice in the industry is to have a container of fuel oil (typically #2 diesel fuel, light cycle oil or kerosene) or some other such solvent attached to the side of paving machine into which the bituminous coated tools can be placed and allowed to passively soak clean. Alternatively, after a period of soaking, the tools can be scraped clean using a putty knife due to the softening effect of the fuel oil or solvent on the bituminous paving mixture.
The petroleum derived fuel oils used to soften and remove bituminous mixture coated hand tools can contain carcinogenic substances and due to the general practice of using the hand tools without gloves the handling of the bituminous mixture coated hand tools there is a greater risk of these carcinogenic substances being absorbed into the bodies of workers.
Better, more environmentally friendly, cleaning methods are needed.